The presence of posterior cerebral artery stenosis indicates that the patient has narrowing of the intracranial blood vessels. The presence of stenosis can be prevented by taking oral medications to prevent the formation of blood clots and slow down the aging of blood vessels. Commonly used drugs include anti-platelet aggregation drugs, such as aspirin and clopidogrel. Lipid regulating and plaque stabilizing drugs such as atorvastatin calcium or resevastatin calcium. When taking the above drugs orally, it is important to observe the side effects of the drugs, such as various bleeding, any muscle pain, and any abnormalities in liver and kidney function. In addition, we should look for risk factors that cause blood vessel stenosis, such as abnormal blood pressure, blood sugar, blood lipids, and homocysteinemia. Blood tests should be performed to rule out hematologic disorders, and symptomatic treatment should be given after risk factors are identified. In addition, cranial angiography can be improved to consider whether surgical intervention is possible.